In Predictably Irrational, behavioral economist Dan Ariely explores how our decisions are influenced by invisible, often illogical forces like expectations, emotions, and social norms, leading us to make consistent and systematic mistakes. Through surprising experiments, he reveals how we overpay, procrastinate, and misjudge situations, showing that these behaviors are predictable and not random. The book offers insights on how to overcome these biases to make better choices in everyday life.